Polyacrylic acid-based fiberglass insulation binders are typically manufactured with a low molecular weight polyacrylic acid, a polyhydroxy crosslinking agent, and a cure accelerator, such as sodium hypophosphite. Typical embodiments include QRXP-1564 and QRXP-1513, produced by Rohm & Haas. QRXP-1564 is a blend of Acumer 1020 (71.6 wt-%), glycerol (21.8 wt-%), sodium hypophosphite (5.6 wt-%), and a small amount of corrosion inhibitor. Water is added as a diluent. QRXP-1513 is a blend of Acumer 1020, triethanolamine, and sodium hypophosphite. Water is added as a diluent. Acumer 1020 is a polyacrylic acid produced from acrylic acid monomer and a sodium bisulfite reactant. Acumer 1020 has a molecular weight of approximately 2000 and a sulfur content of about 3.4 wt-%. U.S. Pat. Nos. 5,340,868, 5,661,213, and 5,763,524, as well as PCT publications WO 100 699 A2 and WO 9 961 384 A1, disclose conventional sulfur-containing polyacrylic acid-based fiberglass insulation binders. See also U.S. Pat. No. 5,318,990.
Recently, insulation binders, produced by polymerizing acrylic acid monomer in water in the presence of a cure accelerator comprising an alkali metal salt of a phosphorous-containing inorganic acid to form a low molecular weight polyacrylic acid and subsequently reacting the low molecular weight polyacrylic acid with a polyhydroxy crosslinking agent in a crosslinking step in the absence of added catalyst, were described by Chen and Downey in an application entitled “Low Odor Insulation Binder from Phosphite Terminated Polyacrylic Acid” that was filed on Mar. 21, 2001 as Ser. No. 09/814,034.
It has been discovered that when polycarboxy polymer-based binders, such as polyacrylic acid-based binders, are applied to fiberglass in the course of manufacturing insulation products, the binder is not spread on the glass fiber as well as are conventionally employed phenol formaldehyde based insulation binders. This poor interfacing/wetting between glass and the polyacrylic acid binder is believed to result from high surface tension due to the strong hydrogen bond of the acid and the acidity of the binder versus the alkalinity of the glass surface. Such high surface tension binders prevent efficient atomization when the binder is applied by spraying it onto glass fibers e.g. in a forming hood, resulting in undesirable droplet size and binder distribution. Once the binder is on the glass fiber, its acidity and high surface tension result in poor wetting and reduced binder flow to fiber-fiber junctions. The poor wetting and reduced bonding efficiency decreases protection of individual glass fibers and results in increased fiber damage during processing. As a result, product properties, including pack integrity and dusting, are adversely impacted.
A recently issued U.S. Pat. No. 6,171,654 (Seydel Research) discloses the incorporation of ethyoxylated tallow amine surfactants into binder made from terephthalate polymers. The Seydel Research patent does not purport to address the above-noted problems.